Convection Currents in the Mantle (Asthenosphere) 1. Heat transfer within a fluid takes place by .
2. Scientists think that convection currents flow in Earth’s .
3. Earth’s mantle is a layer of hot, fluid, tar-like that flows slowly.
4. Which layer is made of the crust and the uppermost part of the mantle?

5 Where does the heat come from that drives the convection currents within the Earth?
6. When a fluid gets hot, the particles gain energy, get excited and . The mass stays the same but the volume increases.
7. This slight increase in volume the density.
8. When a fluid cools, the particles lose energy and . The mass stays the same but the volume decreases.
9. This slight decrease in volume the density.
10. Density = m/v Find the density of hot rock with a mass of 20 and a volume of 10.
11. Density = m/v Find the density of hot rock with a mass of 20 and a volume of 8.
12. When a fluid (like hot rocks at the bottom of asthenosphere) is heated, its density , making them rise.
13. When a fluid (like hot rock at the top of the asthenosphere) cools, its density , making them sink.
14. The asthenosphere is part of which layer?
15. Hot rock is more less dense and .
16. Cold rock is more dense and .
17. Scientists hypothesize that convection currents in the move the large tectonic plates of the .